What is the least common multiple of 40 and 15? Another way to say this is: $\lcm(40, 15) = {?}$
Explanation: The least common multiple is the smallest number that is a multiple of 40 and 15. We know that 40 x 15 (or 600) is a common multiple, but is it the least common multiple? Write out the multiples of 40 until we find a number divisible by 15. 40, 80, 120, So, 120 is the least common multiple of 40 and 15.